Johnson et al., U.S. Pat. Nos. 5,673,252, 5,963,146, 6,172,616, 6,373,399, and 6,653,945 describe a radio-based wireless communication network for sending utility metering data from a plurality of remote devices to a central data terminal through receivers and through intermediate data terminals.
U.S. Pat. No. 6,373,399 further describes an array of receiving stations arranged relative to the remote stations so that the messages from each remote station can be received by at least two and preferably four of the receiving stations. This provides a high level of duplication of messages, which is said to reduce the loss of messages and data.
Many attempts have been made in recent years to develop fixed base network Automatic Meter Reading (“AMR”) systems for the reading of utility meters, such as water, gas, and electricity meters. In each such attempt, the objective has been to provide a level of radio coverage that ensures that all the service modules attached to meters can be read on a daily or more frequent basis, i.e. that the collection of data from the remote service modules is assured for any given period of time.
Fixed base radio networks of the prior art rely on physical placement of transmitters within the range of multiple receiving stations to collect data from remote service modules. It is not possible, however, to exactly define the coverage area of any given receiving station due to difference in terrain and other radio wave interference that may be present at any location. In the typical design for such systems, receiving stations are located such that the remote transmitter modules will be within the range of at least two receiving stations, thereby providing redundant data paths. These systems require the installation of an array of receiving stations arranged relative to the remote transmitters. As a result, the most of the remote transmitters are being received by two or more receiving stations. If there is a reception problem, the physical arrangement must be modified.
It is desired to provide an alternative to this system that would monitor and assure receptions from each transmitter, manage data paths and reduce the amount of duplicate message transmission needed to assure adequate update rates.